Trick-play track via I-frames - AWS Elemental MediaLive

Trick-play track via I-frames

In an HLS output group, you can support trick-play track by providing an I-frame-only manifest.

How the method works

When you create the HLS output group, you create one or more video outputs, in the usual way. For a reminder of the output group structure, look at the diagrams in Organize encodes in an HLS or MediaPackage output group. In the output group, you enable the field to create an I-frame-only manifest that conforms to the HLS specification.

MediaLive produces two child manifests for each encode—one manifest for handling the video in the usual way, and the I-frame-only manifest. The I-frame-only manifest lets the downstream player identify specific video frames to request, to construct the trick-play track. So this trick-play track method doesn't produce additional encodes in the output group.

Each I-frame-only manifest contains the following:

  • One #EXT-X-I-FRAMES-ONLY tag, to indicate that the manifest is I-frame-only.

  • Many #EXT-X-BYTERANGE entries. Each entry identifies the position of an I-frame position.

Setting up

You set up the trick-play track once for the entire HLS output group.

Note

The information in this section assumes that you are familiar with the general steps for creating a channel.

To set up an I-frame-only manifest

Include these steps when you create the HLS output group.

  1. In the HLS output group, in Manifest and segments, for I-frame only playlists, choose ENABLED.

  2. Set up the remaining fields in the output group as you normally would. Set up the video, audio, and captions outputs and encodes as you normally would.